Thermally insulative container sleeve

ABSTRACT

A thermally insulative sleeve is provided. The sleeve is fabricated from a cork-based material. The sleeve is removable and, optionally, reusable. The sleeve is used on the outer surface of a beverage container to insulate the user&#39;s hand from a beverage container and the hot or cold contents therein. A method for insulating a beverage container using a cork sleeve is also provided.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention generally relates to insulative materials. More particularly, the invention relates to a thermally insulative sleeve fabricated from a cork-based, cellulosic material.

2. Description of the Related Art

It is known to provide a thermally insulative sleeve around a container. The sleeve insulates a user's hand from the hot or cold contents within the container. The sleeve also aids in maintaining the contents at a more constant temperature.

In many instances the sleeve is removably placed over the exterior diameter of a beverage container. The sleeve enables a consumer to grasp the beverage container even while the contents are at a high temperature. Such sleeves are most commonly used at coffee bars where paper-based containers are used to serve gourmet coffee, tea or cocoa beverages at hot temperatures.

U.S. Pat. No. 5,205,473 provides an example of a sleeve for a beverage container. The '473 patent issued to David W. Coffin, Sr. of Fayetteville, N.Y. in 1993. This patent is entitled “Recyclable Corrugated Beverage Container and Holder.” The '473 patent discloses a “recyclable, insulating beverage container holder” that utilizes a “corrugated tubular member.” The tubular member is fabricated from a cellulosic material, and offers a series of flutes for containing insulating air. A liner is adhesively adhered along the radially exterior surface of the sleeve to support the flutes and to aid the consumer in holding the beverage.

Column 2 of the '473 patent describes the materials of the sleeve.

-   -   The corrugation can be made of cellulosic materials, including         craft paper, sulfite paper, or recycled paper. Ideally, the         fluting and liners of this invention are adhered to one another         with a recyclable, and preferably, a biodegradable adhesive, for         example, R130 adhesive by Fasson, Inc., Grand Rapids, Mich.         (col. 2., 1. 45-58).

A variety of other patents have issued which disclose the use of an insulating sleeve around a cup. In some cases the sleeve is integral to the cup, while in other instances the sleeve is removable.

The following patents show an integral sleeve: U.S. Pat. No. 1,771,765 (paper); U.S. Pat. No. 2,266,828 (paper); and U.S. Pat. No. 3,908,523 (paper, plastics, foils and metals).

The following patents show a removable sleeve: U.S. Pat. No. 2,617,549 (paper and paraffin); U.S. Pat. No. 2,641,402 (foil); U.S. Pat. No. 5,205,473 (cardboard, paper board or virgin kraft); U.S. Pat. No. 5,454,484 (paper); U.S. Pat. No. 5,425,497 (pressed paper pulp); U.S. Pat. No. 5,857,615 (paper, such as cardboard); U.S. Pat. No. 6,053,352 (thermoform polystyrene); U.S. Pat. No. 6,158,612 (transparent and translucent material); U.S. Pat. No. 6,182,855 (transparent and translucent material); and U.S. Pat. No. 6,250,545 (transparent thermoformable elastic material).

A more desirable material for an insulating sleeve is cork. The term “cork” generally refers to a material that represents the bark of a particular variety of cork oak, quercus suber. This is a tree that belongs to the oak family. The cork oak tree is native to western Mediterranean countries including Portugal, Spain, Algeria, Morocco, France, Italy, and Tunisia. The tree is also found in certain South American countries, particularly Argentina. The cork oak tree is unique in that it has the ability to renew its bark indefinitely.

Cork material is organic and cellulosic. It has been estimated that one cubic centimeter of cork numbers 15 to 40 million hexagonal cells, with the thickness of the cellular membranes varying between 1 and 2.5 microns. Despite this density, the cellular membranes of cork are very flexible, rendering the cork both compressible and elastic. Elasticity enables the cork material to rapidly recover to its original dimensions after any deformation. The tight chemical structure gives cork the property of repelling moisture. The cellular structure coupled with the elasticity of the material has made cork a common material used for stoppers in wine (or other liquid) bottles. More recently, cork bark has been used in the fabrication of floor tiling and insulation. (See, for example, U.S. Pat. No. 6,037,033 offering cork in an insulation panel.)

The value of cork is further increased by its low conductivity of heat, sound and vibration due to the gaseous elements sealed in small, impervious compartments. Cork is also fire resistant, recyclable, and renewable.

A need exists for a container sleeve that is fabricated from a material that is not only biodegradable, but which is renewable. Further, a need exists for a container sleeve that includes a material which provides effective thermal insulation qualities without the need for a corrugated or fluted layer. Still further, a need exists for a sleeve that employs a cellulosic material that includes quercus suber. Finally, there is a need for a light-weight, recyclable, environmentally friendly and aesthetically pleasing beverage sleeve.

SUMMARY OF THE INVENTION

A thermally insulative sleeve for a beverage container is provided. The sleeve in one embodiment includes a substantially planar material fabricated from cork. The material has opposing ends, and is capable of being radially folded into a circumferential object. The sleeve also includes a connector for joining the opposing ends. The connector may be either releasable or may be substantially permanent.

In one aspect, the planar cork material is arcuate in shape such that when the material is folded over, a frusto-conical object is formed. In an alternate embodiment the planar cork material is rectangular in shape such that when the material is folded over, a cylindrical object is formed.

The cork may be a substantially pure sheet of cork. Sheets of cork tend to be flexible which enables them to be rolled and placed into a user's carrying device or, alternatively, collapsed along a pair of folding lines. The cork may alternately be fabricated from a granulated cork composition. In this instance, the opposing ends are held together through an adhesive, with the sleeve being collapsed along a pair of folding lines. Alternatively still, the cork composition is an integral, circumferential object. Further still, the planar cork may define two separate sheets of granulated cork that are connected at opposing ends.

A method for insulating a beverage container is also provided. In one aspect, the method includes the steps of ordering a beverage at a restaurant; receiving the beverage in a frusto-conical container; and placing a thermally insulative sleeve around an outer diameter of the container, the container defining a frusto-conical member having an opening at an upper end and an opening at a lower end for receiving the beverage container. The sleeve, again, is fabricated from cork.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above recited features of the present invention can be better understood, certain drawings are appended hereto. It is to be noted, however, that the appended artwork illustrates only selected embodiments of the inventions and are therefore not to be considered limiting of scope, for the inventions may admit to other equally effective embodiments and applications.

FIG. 1 is a top view of the thermally insulative sleeve of the present invention, in one embodiment. The material in this illustrative embodiment is fabricated from cork sheet. This embodiment presents a substantially planarized material that is arcuate in shape such that when the material is folded over, a frusto-conical object is formed.

FIG. 2 presents a perspective view of the thermally insulative sleeve of FIG. 1. The material has been folded over and the frusto-conical object has been formed.

FIG. 3 shows the thermally insulative sleeve of FIG. 1 folded around a beverage container. A lid is shown exploded away from the container.

FIG. 4 is a plan view of a thermally insulative sleeve of the present invention, in an alternate embodiment. In this embodiment the material is fabricated from granulated cork.

FIG. 5 shows a bottom view of the sleeve of FIG. 4. Here, the sleeve has been folded over.

FIG. 6 is a perspective view of the sleeve of FIG. 4 having been wrapped around a beverage container. Here, the beverage container is a can.

FIG. 7 presents a thermally insulative sleeve of the present invention, in yet an additional embodiment. Here, the sleeve is more elongated and has an open upper end but a closed lower end. Granulated cork is used for the material.

FIG. 8 is a perspective view of a sleeve in yet an additional embodiment. Here, the sleeve is formed by joining two planar cork sheets.

FIG. 9 is a top view of the sleeve of FIG. 8.

DETAILED DESCRIPTION

Definitions

As used herein, the term “cork” refers to any cellulosic material that includes at least 20 percent by weight material from quercus suber.

As used herein, the term “beverage container” refers to a container of any shape or size for holding consumable liquid contents. Non-limiting examples include a styrofoam, plastic, glass, cardboard, or paper cup.

As used herein, the term “carrying device” refers to a pocket, a purse, a brief case, a hand bag, a carrying case or any other carrying device.

DESCRIPTION OF SPECIFIC EMBODIMENTS

FIG. 1 is a plan view of a thermally insulative sleeve 10 of the present invention, in one embodiment. The sleeve 10 is designed and configured to fit around the outer surface of a beverage container (not shown in FIG. 1). The sleeve 10 is fabricated from a substantially planarized material having opposing ends 12 and 14. The material also has an upper side 22 and a lower side 24.

It can be seen that the sleeve 10 has an outer surface 20. Disposed along the outer surface 20 is a wood grain pattern. This is a natural wood grain pattern arising from use of substantially pure cork as the material. Preferably, the material is pure cork stripped from the tree quercus suber. However, any cellulosic material that includes at least 20 percent by weight material from quercus suber is contemplated herein.

Preferably, the sleeve 10 is fabricated from “refugo” bark, that is, a harvest of cork oak bark after the initial, or “virgin” bark is stripped. Refugo bark tends to have a smoother surface, and usually has fewer and more tightly closed pores. This gives the bark an appearance of wood grain. After the stripping process, the bark is usually allowed to dry. Once in the factory area, the cork may be boiled to make the cork more elastic for flattening and stamping. Larger blocks of cork may be cut into thin sheets having the desired thickness.

When planarized or cut cork is used, the material is capable of being radially folded into a circumferential object. The circumferential object is preferably a cylindrical body or a frusto-conical body. In order to acquire the circumferential shape, the planarized material is cut or stamped into an elongated body. The opposing ends 12, 14 of the sleeve 10 are then folded over each other and joined.

FIG. 2 shows the sleeve 10 having been folded into a frusto-conical shape. In order to acquire the frusto-conical shape, both the upper side 22 and the lower side 24 are preferably cut or stamped to have arcuate edges. To then retain the circumferential shape of the sleeve 10, a connector is provided. The connector is not visible in the rolled perspective view of FIG. 2; however, a connector is shown in FIG. 1 at 16. Connector 16 is seen at side 12. It is understood that a reciprocal connector (not shown) may be provided on the opposite surface of the sleeve 10 at side 14.

The representative connector 16 is preferably an adhesive. The adhesive may be a weak adhesive which provides a temporary and easily broken connection between the ends 12, 14. Alternatively, the adhesive may be a strong adhesive which provides a substantially permanent connection between the ends 12, 14. In either instance, the adhesive is preferably a biodegradable or natural adhesive made from a natural rubber latex or rosin. For example, according to the U.S. Agricultural Research Service, a strong and moisture-resistant wood adhesive may be fabricated from a combination of corn starch, polyvinyl alcohol, latex and citric acid. Stuck on Starch, A New Wood Adhesive, Agricultural Research Magazine (April 2000), the article being incorporated herein by reference in its entirety. The natural adhesive is disposed onto a polylactic or other natural film placed along the opposing surface of the sleeve 10 at end 14.

U.S. Pat. No. 5,205,473 teaches the use of a biodegradable adhesive from Fasson, Inc. of Grand Rapids, Mich., referred to as “R130.” Fasson® R130 is a removable adhesive that exhibits moderate tackiness.

Another adhesive that may be employed is a non-toxic adhesive sold under the trademark NICNACTACK®. NicNacTac® Adhesive is available from a company from Los Angeles, Calif. that advertises through the worldwide web at www.nicnactac.com. The adhesive is the subject of U.S. Pat. No. 6,325,885 issued in 2001 to Harrison. According to the '885 patent, the adhesive is a pressure sensitive adhesive based on a dimethylpolysiloxane gum for adhering porous and semi-porous substrates. The adhesive has thixotropic properties which permits the viscosity of the adhesive to break down when pressure from one substrate is exerted on another substrate. The teachings of the '885 patent are incorporated herein in their entirety by reference to the extent not inconsistent with usages herein.

It is to be understood that the present invention is not limited by the type of connector 16 used. The connector 16 may be any type of adhesive. Alternatively, non-adhesive connectors may be used such as a hook-and-loop attachment. The connector 16 is used for joining the opposing ends 12, 14 to form the circumferential sleeve 10. However, biodegradable adhesives are preferred.

An optional additional feature may be provided to the sleeve 10. That pertains to the use of a liner along an inner surface of the sleeve 10 opposite the outer surface 20. FIG. 2 shows a liner 26 as the inner surface of the sleeve 10. The liner 26 is preferably a light-weight piece of woven fabric. However, non-woven materials, leathers, or synthetic leather materials may also be used. The liner 26 provides an even more aesthetic aspect to the sleeve 10 while reinforcing the cork material.

Another optional feature relates to the placement of paper or cardboard material around the outer diameter of the cork sleeve 10. The paper or cardboard material (not shown) may be in the form of a liner that circumferentially encompasses the cork based sleeve 10. Alternatively, the paper or cardboard material could be a smaller piece of material that is applied to the exterior of the cork based sleeve 10. The paper or cardboard material is advantageous as it more readily permits the printing of information such as the trademark of a sponsor or restaurant owner, or advertising material. The paper or cardboard material is preferably applied to the exterior of the cork sleeve 10 by a pressure-sensitive adhesive.

As noted, the sleeve 10 is designed to serve as a thermal insulation device for a beverage container. An example of a beverage container is a paper cup for holding hot coffee, hot tea or other hot beverages. Another example of a beverage container is a plastic cup for holding iced beverages such as iced coffee drinks, smoothies, milk shakes and other cold beverages.

FIG. 3 shows the thermally insulative sleeve 10 of FIG. 1 folded around an illustrative beverage container 30. The beverage container 30 may be a paper or plastic cup, or other type of cup. It may also be a glass container. Typically, the beverage container 30 is a paper container served by a restaurant or coffee bar or smoothie shop. The container 30 has an upper end 34 and a base 32.

When the container 30 holds a hot beverage, the upper end 34 of the container 30 will frequently be served with a lid. An illustrative lid is shown in FIG. 3 at 37. The lid 37 is shown exploded away from the container 30. The lid 37 is configured to snap onto the upper end 34 of the container 30. The lid 37 includes a spout 39 through which the hot beverage may be poured and consumed.

The container 30 of FIG. 3 has an outer surface 36. The outer surface 36 has radially received the illustrative sleeve 10. In the arrangement of FIG. 3, the sleeve 10 immediately engages the outer surface 36 of the container 30. However, the sleeve 10 may alternately engage the outer surface of a cardboard sleeve (not shown) provided by the restaurant or coffee bar.

When the user has consumed the beverage in the container 30, the user will typically dispense the container 30 and any cardboard sleeve provided by the server. However, the insulating cork sleeve 10 is preferably reusable. Thus, the user may take the malleable and foldable sleeve 10 from his or her purse or carrying bag, and place it over the container 30, or over the provided cardboard sleeve and container 30.

U.S. Pat. No. 5,205,473 discussed above provides an example of a sleeve for a beverage container. This sleeve (or others like it) is commonly used in such restaurants as ATLANTA BREAD COMPANY® and STARBUCKS®. However, this sleeve is not fabricated from cork and does not offer the thermally insulative benefits available from cork. Thus, the present sleeve may be used in lieu of or in addition to the cardboard sleeves currently in popular use.

A definition of “cork” was provided above, to wit, any cellulosic material that includes at least 20 percent by weight material from quercus suber. The sleeve 10 shown and discussed in connection with FIGS. 1-3 is fabricated from a substantially pure cork material. However, other types of cork may be used. For instance, granulated cork fabricated from cork particles may be employed. Such a material is commonly used as handle grips, gaskets, and floor or ceiling tiles. Such a material is also used for bulletin boards, and is known as cork board. Such cork material may include at least 40 percent by weight material from quercus suber. Alternatively, the cork may include at least 60 percent by weight material from quercus suber. In one aspect, the cork material includes 60 to 85 percent by weight material from quercus suber. Still further, the cork material may include at least 80 percent by weight material from quercus suber.

In one aspect, a flexible cork composition is fabricated by filling a polyvinyl chloride resin material with cork granules. The thermosetting resin holds the granules together in a flexible structure. However, the cork granules may become dry and brittle as the product ages, so that the resulting product is only slightly flexible without resulting in breakage of the cork granules even though the vinyl binder material itself is flexible.

In order to maintain the flexibility of the composition as the product ages, a plasticizer is preferably used. In one aspect, cork granules are mixed with gelatin, glue and glycerin as a plasticizer for the cork, plus water. However, this composition, after formation, may also dry out due to slow loss of the glycerin from the cork, resulting in shrinkage of the composition.

It is desirable to employ a cork composition wherein the plasticizer in the cork is retained within the cork granules and does not migrate into the binder or matrix of the composition. Thus, in another aspect, the cork granules are plasticized with a liquid organic polyol, and bonded to each other in a flexible plastic binder material. According to U.S. Pat. No. 4,347,272, the loss of glycerin or other polyol-type plasticizer proceeds at a slower rate. Thin sheets of a flexible cork composition may then be produced which retain their flexibility for a long period of time due to inhibition of the loss of the glycerin or other polyol plasticizer from the cork granules.

In one formulation, the material comprises 20 to 50 parts by weight of finely divided cork particles plasticized with 3 to 25 parts by weight of the liquid polyol. The plastic binder material then makes up 25 to 75 parts by weight. Preferably, the cork material represents 40 percent by weight, the liquid polyol represents 15 percent by weight, and the plastic binder material represents 45 percent by weight of the sleeve.

In one embodiment, the cork-based material is fabricated from a combination of granulated cork and other biodegradable cellulosic materials. The cellulosic materials may be paper, cardboard, or paper board. Granulated cork may be laid onto a paper or cardboard substrate and bound with an adhesive. Alternatively, granulated cork may be laid into cellulose fibers, such as through an airlaid process.

Cellulosic fibrous materials suitable for combining with the cork in the sleeves include both softwood fibers and hardwood fibers. Exemplary, though not exclusive, types of softwood pulps are derived from slash pine, jack pine, radiata pine, loblolly pine, white spruce, lodgepole pine, redwood, and Douglas fir. Hardwood fibers may be obtained from oaks, genus Quercus, maples, genus Acer, poplars, genus Populus, or other known pulped species.

The fibrous material may be prepared from its natural state by any pulping process including chemical, mechanical, thermomechanical (TMP) and chemithermomechanical pulping (CTMP). These industrial processes are described in detail in R. G. Macdonald & J. N. Franklin, Pulp and Paper Manufacture in 3 volumes; 2^(nd) Edition, Volume 1: The Pulping of Wood, 1969; Volume 2: Control, Secondary Fiber, Structural Board, Coating, 1969, Volume 3: Papermaking and Paperboard Making, 1970, The joint Textbook Committee of the Paper Industry, and in M. J. Kocurek & C. F. B. Stevens, Pulp and Paper Manufacture, Vol. 1: Properties of Fibrous Raw Materials and Their Preparation for Pulping, The Joint Textbook Committee of the Paper Industry, p. 182 (1983), both of which are hereby incorporated by reference in their entirety.

In one process, a nonwoven material is formed as a continuous airlaid web. The airlaid web is typically prepared by disintegrating or defiberizing a cellulose pulp sheet or sheets, typically by hammermill, to provide individualized fibers. Rather than a pulp sheet of virgin fiber, the hammermills or other disintegrators can be fed with recycled airlaid edge trimmings and off-specification transitional material produced during grade changes and other airlaid production waste. The individualized fibers from whichever source, virgin or recycle, are then air conveyed to forming heads on an airlaid web-forming machine. The fibers are mixed with granulated cork as part of the airlaid process and deposited on the continuously moving forming wire. Where defined layers are desired, separate forming heads or dispensers may be used for each type of fiber or for cork.

Cork compositions may be manufactured according to different thicknesses and qualities. Those of ordinary skill in the art will understand that the quality and sizes of the granules, the type and quantity of the binder, and the compression of the mix (density) determines the quality of the cork composition. Various ways exist for manufacturing composition cork using different resins. Phenolic and synthetic resins can be used depending on the use of the final product. The mixture of cork and binder is poured into a mold, compressed and subsequently heated in an oven. The cork composition is usually developed in sheets, and then cut or stamped.

FIG. 4 is a plan view of a thermally insulative sleeve 40 of the present invention, in an alternate embodiment. In this embodiment the material that makes up the sleeve 40 is fabricated from granulated cork. The sleeve 40 has an upper end 42 and a lower end 44. The sleeve 40 also has opposing ends 46, 48. As with sleeve 10, sleeve 40 is intended to form a circumferential object to be wrapped around a beverage container. However, sleeve 40 of FIG. 4 has different characteristics than sleeve 10 of FIG. 1.

First, as noted, sleeve 40 is fabricated from a granulated cork material rather than a natural cork. The result is that sleeve 40 may not have the flexibility and elasticity of sleeve 10 depending upon the cork composition. This may render sleeve 40 less practical for folding up and carrying in a purse or hand bag. At the same time, sleeve 40 may be collapsed and carried in a user's pocket. Alternatively, sleeve 40 may be collapsed and stacked for shipping to and usage by a restaurant or coffee bar.

In order to effectuate collapsing and stacking of sleeve 40, perforated weakening lines are formed in the sleeve 40. Preferably, two separate lines 41, 43 are provided. These lines 41, 43 allow ends 46, 48, respectively, to be folded under a central body portion 45 the sleeve 40 and then joined together by an adhesive (or other connector) 47.

FIG. 5 shows a bottom view of the sleeve 40 of FIG. 4. Here, the sleeve has been folded over so that ends 46, 48 are under the central body 45 of the sleeve 40. The ends 46, 48 are then joined together by connector 47.

It is also noted that the upper 42 and lower 44 ends of the sleeve 40 are substantially straight, rather than being arcuate. This enables the circumferential object formed by the connection of ends 46, 48 to be cylindrical (or, optionally, square) rather than frusto-conical. This is desirous when the beverage container is itself cylindrical rather than frusto-conical. However, it is understood that the upper 42 and lower 44 edges may also be arcuate to provide a conical shape when folded over.

FIG. 6 is a perspective view of the sleeve 40 of FIG. 4 having been wrapped around a cylindrical beverage container 60. Here, the beverage container 60 is a can. The can 60 most commonly will hold a cold liquid such as a carbonated beverage. The can 60 has a lower end 62, an upper end 67 and a radial outer surface 66. A spout 69 is provided in the upper end so that liquid may be consumed therethrough.

It is noted that the sleeve 40 has both an open upper end 42 and an open lower end 44. In this way the outer surface 66 of the container 60 is circumferentially received by the sleeve 40. Preferably, the sleeve 40 is dimensioned to provide a friction fit around the outer surface 66 of the can 60. However, in an alternate embodiment the connector 47 for the sleeve 40 is releasable, permitting the user to tightly wrap the sleeve 40 around the container 60.

FIG. 7 presents a thermally insulative sleeve 70 of the present invention, in yet an additional embodiment. Here, the sleeve 70 has an upper end 72 and a lower end 74. The upper end forms an opening 76 through which a container such as container 60 may be received. The sleeve 70 also has a cylindrical outer surface 75 and inner surface 78. Unlike sleeve 40 of FIGS. 4-6, sleeve 70 has a lower end 74 that is closed. In this way, the container 60 is received in such a manner that the base 62 of the container 60 is encompassed. This provides still further insulation in order to maintain the liquid therein in a cold state.

The encompassing sleeve 70 may be fabricated from any cork material. The cork material may be either a planar cork such as that shown in FIG. 1, or a granulated cork such as that shown in FIG. 4. The sleeve 70 is again reusable. Where the sleeve material is granulated cork, the sleeve 70 could be fabricated as a single, integral, radial unit without need of joining ends.

The sleeves 10, 40 may serve as an alternative to the well-know cardboard insulating sleeves used by both Starbucks® and Atlanta Bread Company®. This cork sleeve has the advantages of being light-weight, recyclable and reusable. Further, branding could be printed on the outer surface of the sleeve, either directly or onto paper or cardboard material adhered to the outer surface 20 of the sleeve 10.

FIG. 8 is a perspective view of a sleeve 80 in yet an additional embodiment. Here, the sleeve 80 is formed by joining two planar sheets 82, 84. This embodiment is shown with the planar sheets being fabricated from granulated cork. However, a solid sheet of cork or a cork mixed with other cellulosic material may optionally be employed. In the illustrative arrangement of FIG. 8, the two planar sheets 82, 84 are connected by flexible end connectors 86, such as transparent strips of adhesive. The connectors 86 may be on the outer surfaces of the planar sheets planar sheets 82, 84; however, it is preferred that the connectors 86 be in the form of adhesive strips disposed along the inner surfaces of the planar sheets 82, 84 as shown in FIG. 8.

The planar sheets 82, 84 have flexible properties and are capable of being separated so as to form a three-dimensional, frusto-conical object 80. When opened, the sleeve 80 defines an internal chamber region 84 between the planar sheets 82, 84. The chamber region 84 is dimensioned to receive a beverage container such as container 30 of FIG. 3.

The sleeve 80 has an upper end 87 and a lower end 89. FIG. 9 is a top view of the sleeve 80 of FIG. 8. In this view, the upper end 87 is seen. It is also seen that the two planar sheets 82, 84 are placed in immediate contact with one another, allowing the sleeve 80 to be efficiently stacked for packaging and later use. By having two separate sheets 82, 84 of cork-based material joined by end connectors 86, a truly flat and stackable sleeve 80 is provided.

A method for insulating a beverage container is also disclosed herein. In one aspect, the method includes the steps of ordering a beverage at a restaurant, and then receiving the beverage in a container. The container may be any container, including containers 30 or 60. A thermally insulative sleeve such as any of sleeves 10, 40, 70, 80 is placed around the outer diameter of the container. Thus, the sleeve is fabricated from cork.

In one embodiment of the method, the container is a frusto-conical cup, and the sleeve defines a frusto-conical member having an opening at an upper end and an opening at a lower end for receiving the cup. Optionally, the step of receiving the beverage in a frusto-conical container comprises receiving the container with a recyclable cardboard sleeve already disposed around the container. The step of placing a thermally insulative sleeve around the outer diameter of the container then comprises placing the sleeve fabricated from cork around the sleeve fabricated from cardboard.

Alternatively, the step of receiving the beverage in a frusto-conical container comprises receiving the container with a recyclable cardboard sleeve already disposed around the container, and the method further comprises the step of removing the cardboard sleeve before placing the sleeve fabricated from cork around the container.

It should again be understood that the disclosed embodiments are merely exemplary of the inventions, which may be embodied in various forms. Therefore, the details disclosed herein are not to be interpreted as limiting, but merely as the basis for the claims and as a basis for teaching one skilled in the art how to make and/or use the invention. 

1. A thermally insulative sleeve for a beverage container, comprising: a substantially planar material having opposing ends, the material capable of being radially folded into a circumferential object, and the material being fabricated from cork; and a connector for joining the opposing ends.
 2. The sleeve of claim 1, wherein the planar material is arcuate in shape such that when the material is folded over, a frusto-conical object is formed.
 3. The sleeve of claim 1, wherein the planar material is generally rectangular in shape such that when the material is folded over, a cylindrical object is formed.
 4. The sleeve of claim 1, wherein the connector is releasable.
 5. The sleeve of claim 4, wherein the connector is a pair of interlocking slits.
 6. The sleeve of claim 1, wherein the connector is an adhesive.
 7. The sleeve of claim 1, further comprising a fabric liner along an inner surface of the substantially planarized material.
 8. The sleeve of claim 1, further comprising a paper or cardboard material on an outer surface of the sleeve.
 9. The sleeve of claim 1, wherein the substantially planar material is a sheet of substantially pure cork showing a wood grain.
 10. The sleeve of claim 9, wherein the sleeve is flexible and may be rolled and placed into a user's carrying device.
 11. The sleeve of claim 9, wherein the sleeve may be collapsed along a pair of folding lines.
 12. The sleeve of claim 1, wherein the cork is granulated cork held together through a binder.
 13. The sleeve of claim 12, wherein the sleeve may be collapsed along a pair of folding lines.
 14. The sleeve of claim 1, wherein the cork is a mixture of cork and other cellulosic material.
 15. The sleeve of claim 1, wherein the cork includes about 20 to 40 percent by weight material from quercus suber.
 16. A thermally insulative sleeve for a beverage container, comprising an opening at an upper end for receiving the beverage container, the sleeve being fabricated from cork.
 17. The sleeve of claim 16, wherein the cork is a cork composition, and defines an integral, circumferential member.
 18. The sleeve of claim 16, wherein the sleeve defines two separate, substantially planar sheets of cork-based material having an upper end and a lower end, with the planar sheets being connected by a flexible, substantially permanent connector.
 19. The sleeve of claim 1, wherein the planar material is arcuate in shape such that when the material is folded over, a frusto-conical object is formed.
 20. The sleeve of claim 19, further comprising a paper or cardboard material on an outer surface of the sleeve.
 21. The sleeve of claim 16, wherein the sleeve defines a cylindrical shape and has a closed lower end for engaging a bottom of the beverage container.
 22. A method for insulating a beverage container, comprising the steps of: ordering a beverage at a restaurant; receiving the beverage in a frusto-conical container; placing a thermally insulative sleeve around an outer diameter of the container, the sleeve defining a frusto-conical member having an opening at an upper end and an opening at a lower end for receiving the beverage container, the member being fabricated from cork.
 23. The method of claim 21, wherein: the step of receiving the beverage in a frusto-conical container comprises receiving the container with a recyclable cardboard sleeve already disposed around the container; and the step of placing a thermally insulative sleeve around an outer diameter of the container comprises placing the sleeve fabricated from cork around the sleeve fabricated from cardboard. 